1. Field of the Invention
This invention relates to aesthetically pleasing pleasant tasting multicomponent dentifrices and more particularly to a striped toothpaste or gel wherein there is substantially no colorant bleeding between dentifrice components.
2. The Prior Art
Aesthetic effects have been acknowledged to play an important role in consumer acceptance of many products. In many cases, ornamental effects have been used to distinguish particular products in the marketplace and to identify products having particular distinctive properties. In the dentifrice field, toothpastes and gels which have incorporated therein contrasting colored stripes are known. Such stripes provide an aesthetic effect which the user finds pleasing and promotes the use of the dentifrice, particularly by children.
A major problem impacting the aesthetic appearance of striped toothpaste is the bleeding or migration of color from one component into another. This is especially severe if one colored component is applied to the surface of a white base. For this reason, a colorant that exhibits substantially no visible bleeding is required.
Striped dentifrice products containing water-soluble dyes are known in the prior art as for example, as disclosed in U.S. Pat. Nos. 4,358,437, 4,568,534, and 4,487,757. A disadvantage to the use of water-soluble dyes enumerated in these patents is that visible bleeding is observed.
U.S. Pat. Nos. 3,957,964, 3,929,988, 4,071,614 and 4,348,378 disclose dentifrices containing encapsulated ingredients such as flavors whereby such ingredients are maintained substantially separate from other dentifrice ingredients during manufacture and storage, while subsequently releasing the encapsulated ingredients into the dentifrice during tooth brushing.
It is also known to the art, e.g., U.S. Pat. No. 4,202,878 to encapsulate water insoluble dyes in capsules wherein the shell material is formed from non-toxic naturally occurring waxes such as carnauba wax, candelella wax, castor wax, paraffin wax and bayberry wax. Although encapsulation of the dyes in these natural waxes overcome dye migration and bleeding, waxes such as natural paraffin wax, have been found to have the drawback, that the wax encapsulated dye when incorporated in a dentifrice composition produces an undesirable, waxy-plastic-like taste when stored at room temperature and during accelerated aging conditions, as for example, 6 weeks at 50.degree. C.
Accordingly, there is a need for a colorant composition useful in the striping of aqueous based dentifrices which will essentially eliminate visible colorant bleeding and which does not suffer from the limitations and problems of the prior art.